EPA on-scene coordinator explains what caused last week's rupture
GOLD KING MINE, COLO. — Environmental Protection Agency officials met at the mouth of the Gold King Mine Monday afternoon to discuss last week's breach, which discharged 3 million gallons of heavy-metal laden water into a tributary of the Animas River.
EPA on-scene coordinator Hayes Griswold explained to San Juan County, Colo., officials that an EPA team working at the mine on Wednesday underestimated how much pressure was hidden behind the debris that plugged the mine's entrance.
He said the team was not attempting to dislodge the plug, but was instead attempting to stick a pipe into the top of the mine.
The pipe would allow the team to safely pump liquid out of the mine for treatment, Griswold said.
"We were very careful," he said, adding that he has 28 years of mining experience.
However, the team removed too much material from the mine's roof, which caused the rupture, Griswold said.
As reported, mustard colored water polluted with toxic waste poured from the mine and emptied into nearby Cement Creek, which drains into the Animas River.
The polluted waters were carried along the Animas River through Durango and then flowed into the San Juan River at the confluence of the rivers in Farmington on Saturday morning.
Griswold was joined at the Gold King Mine Monday by Martin Hestmark, an assistant regional administrator for EPA Region 8.
Hestmark warned Griswold about allowing another such incident to occur and said they would need to discuss ways to contain the many mines that pockmark the mountains surrounding Silverton.
"One of the things the community will not tolerate is this happening again," Hestmark said.
Griswold said Monday that the mine was discharging anywhere between 200 to 700 gallons per minute of polluted water.
The fluctuation in discharge was caused by cave-ins within the mine, which may temporarily slow the flow rate, Griswold said.
The water flowed down the mountain pooling in one of several man-made ponds a few thousand feet below the mine's mouth where contractors treated it with lime, coagulants and caustic soda.
Griswold said he believed there were other mines in the area that posed a similar threat of rupturing.